if(mouse_check_button_pressed(mb_left))
{
    if(global.player1Stats[4] == 1)         // depending on upgrade, spawn bullet
    instance_create(self.x,self.y, playerBullet1_obj);
    if(global.player1Stats[4] == 2)
    instance_create(self.x,self.y, playerBullet2_obj);
    if(global.player1Stats[4] == 3)
    instance_create(self.x,self.y, playerBullet3_obj);
    if(global.player1Stats[4] == 4)
    instance_create(self.x,self.y, playerBullet4_obj);
    if(global.player1Stats[4] == 5)
    instance_create(self.x,self.y, playerBullet5_obj);
}
